Loading and unloading external swfs

Hey,

I am making a website that will have many levels of externally loaded swfs.

  1. How do you load and unload the externally called swfs with either an animation within the swf movie, or through the AS when you call it.

  2. I will have my navigation loaded on a top level and everything else loaded below. When I click on another Button from my navigation that will load another swf movie- How do I unload the swf that is previously there?

Any help would be appreciated and hopefully this is understandable!

Thanks for your time,

Chris.